Caspar Oesterheld (2018): Newcomb's Problem, the Prisoner's Dilemma and Large Universes: a Consideration for Consequentialists. Talk at the 15th Conference of the International Society for Utilitarian Studies, Karlsruhe Institute of Technology (KIT), July 24-26, 2018. (Abstract), (Slides).

Some papers closely related to multiverse-wide superrationality can be found in section 6.1 of the 2017 paper.